The use of wireless communication links, whether for video, voice, or data, have become prevalent in recent years, particularly in light of the widespread adoption of mobile technology, such as cellular telephones, laptop computers, personal digital assistants (PDAs), pagers, and the like. Wireless communication links are particularly desirable with respect to some situations, such as to avoid obstacles associated with laying cable between communication nodes, providing freedom of movement, etcetera. Accordingly, wireless communication links have been given much consideration by communication infrastructure providers. However, deploying wireless communication links is not without difficulty. In particular, wireless spectrum is often highly regulated and may be prone to interference.
Wireless broadband access has been considered quite extensively in recent years. Although multiple solutions have been experimented with, attempts at providing wireless broadband access, particularly widespread access, has generally not met with commercial success due to inadequate economical conditions, i.e., high cost without sufficient demand. In particular, the need for licensed spectrum in which to provide wireless links has typically resulted in high costs to wireless broadband access providers. Moreover, past wireless broadband access solutions have typically implemented non-standard or application specific equipment, due to each provider developing a unique solution tailored to their particular solution, circumstances, and spectrum, thereby preventing economies of scale and compatibility.
Demand for such wireless broadband access has generally been associated with applications and appears to be correlated to at least some degree to the cost of the service and equipment, the complexity of the implementation, and the reliability of the links. The proliferation of wired broadband access, such as via cable modem and digital subscriber line (DSL), is stimulating the creation of applications requiring relatively large amounts of bandwidth, such as music downloading, video streaming, multi-media presentations, etcetera. However, a large number of nodes desirous of implementing such emerging applications are not yet wired for broadband access and, therefore, cannot adequately access such applications.
Two related wireless technologies are beginning to gain acceptance in providing at least some level of wireless broadband access, these being wireless technologies based on the Institute of Electronic and Electrical Engineers (IEEE) 802.11 and 802.16 standards. The 802.11 standard is directed toward indoor applications and sets forth asynchronous protocols for short range communications, while the 802.16 standard is directed toward outdoor applications and sets forth synchronous protocols for longer range communications, each being operable in unlicensed spectrum such as within the 2 to 11 GHz range. Implementation of such standards facilitates equipment cost reduction by providing for compatibility and economy of scale. However, technologies adopting the foregoing standards heretofore have not adequately addressed the issues associated with commercial or economic deployment of wireless broadband access. For example, although addressing aspects such as communication protocols, the standards alone do not provide for spectrum utilization suitable for reliable or large scale wireless broadband access.
Traditional wireless services rely upon licensed spectrum, in which the use of the spectrum is highly regulated such that sources of interference are avoided, in order to provide for spectrum utilization suitable for reliable or large scale access. However, that spectrum is expensive and is very difficult to obtain. Unlicensed bands, although providing a readily available and inexpensive alternative, present a cost in that the spectrum is open to many simultaneous uses and thus prone to interference leading to link degradation and even blocking. Such disadvantages are particularly prevalent in outdoor applications, where interference from uncontrolled sources can travel long distances, substantially unimpeded.
Accordingly, a need exists in the art for systems and methods providing for utilization of spectrum suitable for reliable and/or large scale wireless access. Particularly, a need exists in the art for systems and methods which mitigate interference with respect to wireless communication links, such as those operable in unlicensed bands.